Final answer:
The DC loadmeter can be used as both an ammeter and a voltmeter with various full-scale readings.
Step-by-step explanation:
The DC loadmeter can be used as an ammeter and as a voltmeter with different full-scale readings. For an ammeter, it can be used with a 20.0-A full-scale reading and a 100-mA full-scale reading. As a voltmeter, it can be used with a 300-V full-scale reading and a 0.300-V full-scale reading. Additionally, it can be used as an ammeter with a 300-mA full-scale reading when connected to a 25.0-Ω galvanometer with a 50.0-μA sensitivity.